Speed changing apparatus



May 10, 1932. T. oKUMURA 1,857,324

SPEED CHANGING APPARATUS Filed Aug. l5,` 1928 2 Sheets-Sheet l May 10, 1932. T. OKUMURA 1,857,324

SPEED CHANGING APPARATUS Filed Aug. l5, 1928 2 Sheets-Sheet 2 Patented May 10, 1932 UNIT-En STATES TAKESHI OKUMURA, OF. KAMIKYQ KU, KYQTQ'. JAPAN" SPEED CHANGING APraRA'rUs i Application ledfAugnst 15, 71928,- Serial- No.`299;822,2 and inLTapanfAiug'ustA 19,' 1822.",

rI"his invention relates to a speed changing apparatus comprising a plurality of rim-imits arranged slidably along radial slots of a'pair of dises which: are mounted on the driven shaft in such a'manner as -to slide alongbut L" to rotate together With said shaft.l It is also provided with.v the means tocauseall the rim unitslto. move to its outer or inner position, thus enlarging or diminishing the diameter of therpull'ey formed by said rim units.

The apparatus has also Vbalancing means which, when the diameter of the driven pulley is diminished andconsequently the speed is increased, balances or absorbs the side thrust on the bearings due to theincreased speed.

A primary object of this invention is to obtain a speed changing apparatus which, in spite `oi the constant speed of the driving shaft, enables even unskilledl hand to change i' 20 the driven speed at full range from the minimum to the maximumV by aneasy and'rapid manipulation.

The other object of this invention i's to obtain a'simple and effective means forbalancing the side thrust due to the increasingfspeed and for preventing `the damage ot thefbearingsand their associated parts, sothat the machine may keep a long/life.

The accompanying drawingsv show diagrammatically an example of the construetions acoording'to this invention, but it is clear Ythat the invention is Anot'limited to such a construction.

In the drawings, Y

Fig. 1 is` a sectional elevationjo-"the apparatus according to this invention;

Fig. 2, a side vieW of the same;

Fig. 3, a diagrammatic vieW- showing-the driving connection; l

Fig. 4, a sectional elevation of fa modification of the apparatus having balancing' means; v

Fig.Y 5, a side view otlieYsame-'partlyrcut E Fig, 6, a sectional elevation of fanothlel modification;

Fig; 7 is a side vieWo the sameipartly eut OH' y Fig. 8,l the' sectional: elevation ofganother g fniodification;

Eig.; 9, ,a iside Viewl ofthe .sameewthfoits .upperhalfcut oj EigmlOLis a. plan viewof onefof ithe. bell crank levers.-` l

i Referring to-'Figs 1;and25 2.; is aY pai-r` of encuiar' fdiscs; mountedioppositely 011;: the diiverr shaft :I to..rotate.xt ogethe1 yvriclnizi': 3 isarimunit inountedon the inner Opposite surfaces. of. a pail` f' off.. dises; g2'. and. slidable along the,opposite.radialigrooves 2Q. Aling or collarQl is mountedgbetween the hubsi22 of the rotatingv dises 52 and provided fon its peripheryl vvith illi'gsrk,eachr of. whlllrs; con: nected'by links 9',` 9 and?, 7;; vWitira central pivot 23k onga rim-,unit kThe `joints 24 and 24 between-2 the links 1 7 9,; and 9` are connectedjby links 8 anldlSf With-apair'oiiflugs 10, 104 'eacln of; which is; onY the iside bearings 54 andi, through the opcningggs.v .140i the1 discs 2,. 'Rings ,6, and'aremounted on thelbear.-

fings'andz 5- to enablafthe@ bearings tobe shifted axially o1'1 tli.e-fshaft l byY any suitable means associated ,Wthasaidiringg A v Fig. 3 shows the mode., of` driving the drivenxshafft l froniithedriving shaftl 30. The endless fbelt leconnecting the`v driving pulley 29 on-,zthesshaft 80: with thedriven pulley according-to this inventionz(up on the driven shaft` l) is ftightenfedby a .tension device consisting. of a pressing roller12aand a4 Weight i' .Y 13 each mounted on a lever so that the change `of the diameter oflthfe driven pulley does-not aiect'the tensionioi fthe belt.`

In this formi of theinventiomthe .diameter of the driven pulleysr may be changed in; a Wide range from themaximum.tor the minimum by shiftingV the bearings and 5f from their ir'inerinost tooutermosty position by lrings Gand 6"V and other suitabkleemeans.Vv Gonsequently, the speed oi? the driven shaft and I its associated` parts may' be changed Widely vonly by a shiftingoperation of thebearings ,'Without changingthe speed and 4diameter-lof the driving part. Y

In theemhodiment shown iin Figs. `Il: and 5,

apairiof discs2 isso formedas to have coni-v cal surfaces at their' opposite, inner surfaces,

on which a plurality .ofradial guide grooves p arecut or formed.r i lAninclined:leg'32r at either side of the rim unit 31 is inserted in a guide groove so as to slide along it.

A plurality of bearings 33 are fixed on or formed integrally with the inner lower face of the disc 2. On each bearing33 a link 34 is pivoted to swing radially. With the free ends of a pair of links 34 is connected a balancing weight 35 which has a central aperture 38 and can be moved into or out radially along a guide rod 37 fixed to the periphery of a ring 36V mounted`r on the shaft 1 midway between the discs 2.

Shifting the bearings 5 inwardly and thus lbringing, the discs 2closer, all the rim units 31 are moved outwardly at the same time and 'the same rate, increasing the diameter of the driven pulley constructed by said rim units. In thiscase, the balancing weight 35 is moved toward the central axis by the downward swing ofthe links 34. Thus, when the diameter of the driven pulley is increased and consequentlythe speed reduced, the centrifugal action of the rim units exerts little thrust which may beneglected accordingly. In this case, balancing weights 38 are close to the axis. Its centrifugal action due to the rotation of the shaft 1 is also small and has no appreciable effect. However, if the diameter of the pulley isreduced by parting the discs 2 and consequently the speed of rotation is increased, the balan'cingweight 38 comes out radially along' the guide rod 37. Then,the centrifugal action of the rim units tends to exert great lateral thrusts on bearings, but

at the same time'the centrifugal action of the balancing weight 38 which also increases materially in this case, balances or equalizes the thrust, thuspreventing the thrust from damaging the bearings. Y

In the vembodiment shown in Figs. 6 and 7, a rim unit 31 shown t0 form a rope pulley is guided slidably along the radial grooves 20 of the rotating discs 2 arranged and mounted on the driven shaftl in the same whichengages with the inclined flange 44 of the arm of a rim unitr31.

On the outer surface of a disc 2 a plurality of pockets are arranged radially.V A sliding weight 47fis`slidably guided in' each pocket 50, it being connected by a flexible band 45 with the sliding disc 40 through the Vopening 46 cut through the outer disc 2. The

sliding disc 40 is. connected with the bearing f5 by several bolts 48 passingv throughv the apertures 49 in the outer disc-40.

If the bearings 5 are shifted inwardly, the

sliding discs 40 come close to each other, pushing the rim units 31 outwardly along the guide grooves on the discs 2, and permitting the weights 47 to fall along the pockets 50. Thus, with the increased diameter of the driven rope pulley and the diminished speed of rotation, the thrust due to the rotation of the pulley is small and the balancing weights 47 have little effects. When the sliding discs 40 are shifted apart and the rim units are moved inwardly as shown by full lines, the speed of rotation of the diminished pulley is considerably increased, producing material Vthrusts on the bearings., In this case, however, the balancing weights 47 are pushed outwardly and the inertia of these weights is sufliciently increased to tionable thrusts. Y

In another embodiment shownvin Figs. 8, 9, and 10, a plurality'of rim units 31 are equalize the objecof the innerl surfaces of a pair of opposedlyarranged rotating discs 2 in the same way as already shown in Figs. 1 and 2. Y

Referring to Figs. 8 to 10, 51 is a bell crank `mounted slidably along the radial grooves lever one end ofwhich is inserted through rectangularradial hole 14. The arm 52 of the lever 51 extending inwardly through said hole is bi-furcated-as shown in Fig. 10, the

bi-furcated arms being pivotedto arms '53..

of two adjacent rimunits 31. The lever 51 is pivoted to a stationary shaft 54. The other arm 55 of the lever is connected with'a bearing 5. The bell crank lever 51'Uis loaded with a balancing weight 57 on its shoulder.

When the rim units 31 are moved outwardly and take the position shown by dotted lines in Fig. 8, the speed of rotation is minimum and the centrifugal force exerting axial thrusts are very4 small.

shown ,by dotted lines and the balancing weight 57 comes close tothe shaft 1. When the diameter of the pulley is reduced to that `shown by full lines, the rotation of the pulley considerably increases, causing the side -57 moves away further from the shaft 1, the

VIn this case, bell, -crank lever 51` comes to the position also centrifugal action of the weight vincreases rapidly and sufficiently equalizes thel side thrusts caused by the rapid rotationof the pulley. y,

I claim:

V1. Speed changing apparatus comprising a plurality of rim units slidably engaged in .radial slots of a pairof opposed discs rotatable on a rotating shaft, a ring fixed to the shaft, guide rods fixed to the ring, balan'cinor weights slidably guided on said'rods,rand

discs. g' 2. Speed changing'rapp'aratus comprising opposed discs rotatable on a rotating shaft,

"links pivotally connecting the vweights and f rim units slidable radially between the discs,- means for shifting the rim units radially of the shaft, radial guides associated with the discs, Weights sldably guided by the guides, the radial thrust of the rim units being counteracted by the centrifugal force of the Weights.

In testimony whereof I have affixed my signature.

TAKESHI OKUMURA. 

